One person in particular, Gopal, was already building something with the web service. I had been in contact with him previously over email and had heard about his application. He invited me down to his desk to have a look and to help debug a few things. What I saw caused my jaw to drop. Gopal had built a XUL interface to Yahoo! Mail using the web service for communication with the backend. It was fast, it was pretty and he had managed to pull off client-side message threading.

Gopal’s post has more details on how he built Tapestry, as well as links to code. Very cool!